Private equity interests were all set to buy Sallie Mae (NYSE: SLM). Now, in light of tight credit for buying big companies, the investors want a better price. It may be that Wall St. saw it coming. After the stock hit a 52-week high of $58, "shares of SLM closed yesterday at $48.55, because investors expect a price cut," according to The New York Times.

The private equity firms involved, J. C. Flowers & Company and Friedman Fleischer & Lowe, are going to try to go back to the company to reset a the purchase price. It is not clear how much of a haircut they want the Sallie Mae shareholder to take. The total value, based on the current offer is $25 billion. The New York Times also reports that there is a $900 million break-up fee due to the company if the buyers walk.

The news is further evidence that private equity buy-outs of large public companies are dead, at least for the time being. The banks and institutional investors which provide the debt for these deals do not want to take on any more risk for leveraged financings that could collapse if a company misses its numbers.

The news will be especially hard on anyone who owns a share or two of the student loan company. When the deal was first announced in April, Sallie Mae shares moved from $41 to $56 in a matter of days. When credit markets got choppy in July, those shares began to fall.

Now, they may go even lower.

Douglas A. McIntyre is a partner at 247wallst.com.